Chap. 26. Of Youth, or Growth.
THus Spirits of sense work according to the substance of the matter: for if the matter be porous and light, they form those figures quicker, and dissolve them suddenly: But if their matter be solid and hard, they work slower, which makes some figures longer ere they come to perfection, and not so easily un∣done. And if their strength be too weak for the matter they work upon, as wanting help, then the figure is imperfect, and mishapen, as we say. This is the reason Animals and Vegeta∣bles, which are yong, have not so great strength as when they are full grown; because there are fewer spirits, and the mate∣rials are loose and unsetled, not knockt close: But by degrees more spirits gather together, which help to forward their work, bring in materials by food, setling them by nourishment, carrying out by Evacuations that matter that is unuseful, and that Rub∣bish and Chips, as I may say, which would hinder their mo∣tion. If they bring in unuseful matter, their figure increases not, as we say, thrives not. And if they carry out the princi∣pal materials, the figure decayes, and falls down. But those parts of matter which are not spirits, do not carry that part of matter which is spirit, but these spirits carry the dull matter. Thus the spirits, the innated matter, move in dull matter, and dull matter moveth by the spirits; and if the matter be fine, and not gross, which they build withal, and their motion be regular, then the figure is beautiful and well proportioned.